Interleukin-15 receptors

Abstract

There are disclosed Interleukin-15 Receptor (IL-15R) proteins, DNAs and expression vectors encoding IL-15R, and processes for producing IL-15R as products of recombinant cell cultures.

What is claimed is:  
     
       1. An isolated DNA encoding an IL-15 receptor (IL-15R), wherein the DNA is selected from the group consisting of: 
       (a) a DNA having a nucleotide sequence as set forth in SEQ ID NO:1, nucleotides 91 through 789;  
       (b) a DNA having a nucleotide sequence as set forth in SEQ ID NO:6, nucleotides 34 through 753;  
       (c) DNAs that hybridize to the DNA sequences of (a) or (b) or their complementary strands under conditions of moderate stringency (50° C., 2×SSC), and which encode polypeptides capable of binding IL-15; and  
       (d) DNAs that, due to degeneracy of the genetic code, encode polypeptides encoded by any of the foregoing DNAs.  
     
     
       2. An isolated DNA according to  claim 1  that encodes a human IL-15R. 
     
     
       3. An isolated DNA according to  claim 1  that encodes a soluble IL-15R. 
     
     
       4. An isolated DNA according to  claim 3  wherein the DNA is selected from the group consisting of: 
       (a) a DNA having a nucleotide sequence as set forth in SEQ ID NO:1, nucleotides 91 through 612;  
       (b) a DNA having a nucleotide sequence as set forth in SEQ ID NO:6, nucleotides 34 through 567;  
       (c) a DNA that encodes a fragment of a peptide encoded by the sequences of (a) or (b), which fragment is capable of binding IL-15;  
       (d) DNAs that hybridize to the DNA sequences of (a), (b) or (c) or their complementary strands under conditions of moderate stringency (50° C., 2×SSC), and which encode a polypeptide capable of binding IL-15; and  
       (e) DNAs that, due to degeneracy of the genetic code, encode a polypeptide encoded by any of the foregoing DNAs.  
     
     
       5. An isolated DNA sequence according to  claim 3  that encodes a human IL-15R. 
     
     
       6. An isolated DNA according to  claim 1 , encoding a modified IL-15R polypeptide having one or more changes in a primary amino acid sequence, which changes are selected from the group consisting of: inactivated N-linked glycosylation sites; modified KEX2 protease cleavage sites; deleted cysteine residues; and conservative amino acid substitutions, wherein the modified polypeptide binds IL-15. 
     
     
       7. A recombinant expression vector comprising a DNA according to  claim 1 . 
     
     
       8. A recombinant expression vector comprising a DNA according to  claim 4 . 
     
     
       9. A recombinant expression vector comprising a DNA according to  claim 5 . 
     
     
       10. A process for preparing an IL-15 receptor (IL-15R), comprising culturing a host cell transformed or transfected with a recombinant expression vector according to  claim 7  under conditions promoting expression, and recovering a polypeptide from the culture, wherein the polypeptide is capable of binding IL-15. 
     
     
       11. A process for preparing an IL-15 receptor (IL-15R), comprising culturing a host cell transformed or transfected with a recombinant expression vector according to  claim 8  under conditions promoting expression, and recovering a polypeptide from the culture, wherein the polypeptide is capable of binding IL-15. 
     
     
       12. A process for preparing an IL-15 receptor (IL-15R), comprising culturing a host cell transformed or transfected with a recombinant expression vector according to  claim 9  under conditions promoting expression, and recovering a polypeptide from the culture, wherein the polypeptide is capable of binding IL-15.